287981591 has 2 divisors, whose sum is σ = 287981592. Its totient is φ = 287981590.

The previous prime is 287981567. The next prime is 287981593. The reversal of 287981591 is 195189782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 287981591 - 2⁶ = 287981527 is a prime.

Together with 287981593, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (287981593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 143990795 + 143990796.

It is an arithmetic number, because the mean of its divisors is an integer number (143990796).

Almost surely, 2^287981591 is an apocalyptic number.

287981591 is a deficient number, since it is larger than the sum of its proper divisors (1).

287981591 is an equidigital number, since it uses as much as digits as its factorization.

287981591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 50.

The square root of 287981591 is about 16970.0203594457. The cubic root of 287981591 is about 660.3713788359.

The spelling of 287981591 in words is "two hundred eighty-seven million, nine hundred eighty-one thousand, five hundred ninety-one".